Inductor current relay switch

ABSTRACT

An inductor relay switch ignition system for an internal combustion engine having a vehicular electrical system incorporating an ignition coil, a battery and a pair of intermittently-opened breaker points, includes a lead connecting the positive terminal of the coil with the battery, a neon lamp connected by a lead to the battery on one side and to the negative coil terminal on the other side, a resistance connected at the battery side of the lamp on one end, an NPN transistor connected at its base terminal to the other end of the resistance, a second resistance connected at the battery side of the lamp on one end and a second NPN transistor connected at its base terminal to the other end of the latter resistance. A common lead connects the collector terminals of both NPN transistors with the other side of the lamp. Also, a PNP transistor has a lead connecting its base terminal with the emitter terminal of one of the NPN transistors, a lead connecting its emitter terminal with the emitter terminal of the other NPN transistor, and a lead from its collector terminal is connected to ground. The lead connecting the base PNP transistor terminal with the NPN transistor emitter terminal also is connected to one of the breaker points. Finally, the second breaker point is connected with the ground lead.

States 386118 1 Crisafulli, Sr.

I54] INDUCTOR CURRENT RELAY SWITCH [76] Inventor: Peter G. Crisafulli, Sr., 1438 France Lane, Plainfield, NJ. 07062 [22] Filed: June 8, 1971 [21] Appl. No.: 150,959

[52] US. Cl ..l23/148 E, 123/148 R [51] Int. Cl ..F02p 1/00 [58] Field of Search ..'.....l23/l48 E [56] References Cited UNITED STATES PATENTS 3,045,148 7/1962 McNulty ..l23/l48 2,916,672 12/1959 'Segall ..l23/l48 3,202,904 8/1965 Madland ..l23/148 3,291,109 12/1966 Neapolitakis ..123/148 3,374,778 3/1968 Pixon 123/148 3,379,182 4/1968 Rittmann. .....l23/148 3,394,689 7/1968 Bell ..123/148 3,422,804 1/1969 Van Mastrigt ..l23/l48 3,504,230 3/1970 Gaddes ..123/l48 3,599,618 8/1971 Schuette ..123/l48 3,584,929 6/1971 Schuettc l1 ..l23/l48 Primary Examiner-Laurence M. Goodridge Assistant Examiner-Ronald B. Cox Att0rneyPeter J. Gaylor [57] ABSTRACT An inductor relay switch ignition system for an internal combustion engine having a vehicular electrical system incorporating an ignition coil, a battery and a pair of intermittently-opened breaker points, includes a lead connecting the positive terminal of the coil with the battery, a neon lamp connected by a lead to the battery on one side and to the negative coil terminal on the other side, a resistance connected at the battery side of the lamp on one end, an NPN transistor connected at its base terminal to the other end of the resistance, a second resistance connected at the battery side of the lamp on one end and a second NPN transistor connected at its base terminal to the other end of the latter resistance. A common lead connects the collector terminals of both NPN transistors with the other side of the lamp. Also, a PNP transistor has a lead connecting its base terminal with the emitter terminal of one of the NPN transistors, a lead connecting its emitter terminal with the emitter terminal of the other NPN transistor, and a lead from its collector terminal is connected to ground. The lead connecting the base PNP transistor terminal with the NPN transistor emitter terminal also is connected to one of the breaker points. Finally, the second breaker point is connected with the ground lead.

PATENTEUJUH 5 I975 3,736,913

I NVENTOR.

PETER G. CRISAFULLI. SR.

ATTORNEY BACKGROUND OF THE INVENTION To ignite a combustible mixture in the cylinder of an DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will be more readily understood by refautomobile, there are required in the neighborhood of 5 erence to the drawing in which the ignition coil of a car 22 kilovolts under worst-case conditions. Furthermore, a minimum of about millijoules of energy are needed at the spark plugs to insure flame propagation originating from the spark. Thus, it is apparent that the distributor points of a car are subject to severe conditions. Since a maximum current of about 4 amperes can be withstood by the points before complete burn-out occurs, there is no surprise that such points require frequent replacement so as to maintain full ignition coil efficiency.

Various transistorized ignition systems have been proposed in the art to control the coil current and thus reduce the load on the distributor contacts. For example, U.S. Pat. No. 3,307,073 proposed to do this by introducing a pair of damping coils into a transistorized circuit between the ignition coil and the distributor points. Besides the added weight of the unit, the system effects only a partial solution to the problem. In US. Pat. No. 3,259,1 18, a transistorized system is proposed wherein a large capacitor is introduced for effecting the discharge. such a circuit is not only complicated, but also expensive. Another proposal, in US. Pat. No. 3,363,615, effects the closure of the transistorized circuit electronically and does not wait for the points to close and build up coil current. This circuit also is cumbersome and expensive.

BRIEF DESCRIPTION OF THE DRAWING In the accompanying drawing, there is depicted a schematic diagram of a preferred embodiment of a transistorized ignition system of the present invention, as applied to an internal combustion engine.

SUMMARY OF THE INVENTION According to the present invention, a relatively simple transistorized circuit is employed to reduce the current fed to the distributor points to a value of about I ampere, or less, while still maintaining full amperage (about 4 amperes) in the ignition coil, whereby full coil efficiency is maintained. By this means, reduction in coil efficiency by arcing and severe burning at the distributor points is reduced, or even practically eliminated. In the present invention, the coil current is allowed to pass through a neon lamp electrode, at which point the current is split, one branch passing through a resistance and an NPN type transistor, then to a PNP type transistor and to the negative ground. The other split current passes through another resistor and an NPN type transistor, then through the distributor points and to the ground. This latter current is also led to the base of the PNP transistor.

The collector terminals of the two NPN transistors are connected at the other neon lamp electrode. In this way, the neon lamp serves to drain any kick-back voltage in excess of that which the transistors can handle. Furthermore, the brilliance of the neon lamp, due to changing voltage impressed thereon, is a good indicator of any faulty condition in wiring, spark plugs or engine performance. A dull glow of the lamp indicates satisfactory performance.

Such a system has been found to reduce tune-up costs of conventional cars by as much as 60 percent.

engine is indicated by the numeral 10. Lead 11 of the coil is the high voltage line connected to the spark plugs (not shown). The positive low voltage lead 12 from coil 10 is connected to the positive terminal 13 of battery 14 (say, 12 V). From battery anode 42, a line 15 is connected to a terminal 16 between two resistors 17 and 18, at which a current split occurs. Part of the current from terminal 16 passes through resistance 17 (having a value, say, of ohms), and then it enters via line 19 to the base connection of NPN transistor 20. The other portion of the current from terminal 16 passes through resistance 18 (having a value of, say 270 ohms), after which it passes, via line 21, to the base connection of NPN transistor 22. Both collector terminals of transistors 20 and 22 are connected by line 23.

A neon lamp 24 (say one of type NE2I-I), is con nected at one terminal by line 25 to the common resistance terminal 16. The other terminal of lamp 24 is connected, by line 26, to common lead 23 at 27, and then, by line 29, to the negative low voltage terminal 28 of coil 10. The emitter terminal 30 of transistor 22 is connected by line 31 to one distributor point 32.

Emitter terminal 30 of transistor 22 also is connected, by line 33, to the base connection of PNP type transistor 34. The collector terminal 35 of transistor 34 is connected to the negative ground 36 by line 37. Distributor point 38 is connected by line 39 to line 37 which leads to ground 36. Both emitter terminals of transistors 20 and 34 are connected by common line 40. A conventional condenser 41 is connected between distributor points 32 and 38.

In operating the unit, when distributor contacts 32-38 are closed, a small current, controlled by resistance 18, is conducted to ground 36, and the load from line 29 of coil 10 passes lightly to ground 36 through transistor 22. At the same time, distributor contacts 32-38 turn on transistor 34 as well as transistor 20. Transistor 34 draws heavily through transistor 20, as controlled by resistance 17, thereby raising the current (drawn through the load across coil terminals 1228) up to the required operating level, usually about 4 amperes.

Neon lamp 24 serves as a twofold member. First, it controls the inductive kick-back to a safe level within the operating range of the transistors. Secondly, lamp 24 flickers with a dull glow when the engine ignition system is operating properly. However, if lamp 24 acquires a full brilliance, this is an indication of faulty wiring or spark plug fouling, or faulty engine performance, which results in high voltage (built up by the transformer when contacts 32-38 are open), which is not dissipated through the ignition wiring and spark plugs.

By operating the distributor points at about 1 ampere, according to the present invention, instead of the conventional 4 amperes, there is less chance of point bounce caused explosions of the are formed between the points. Also, a value of l ampere is sufficient for burning away any insulating oxidation film which may build up at the points.

In a test of the system, control resistors 17 and 18 were increased in value nearly 50 percent to allow only 2% amperes to flow through the coil, instead of 4 amperes. Yet, the engine started readily and operated without difficulty at F.

Whereas a conventionally ignited engine often fails to deliver adequate sparks on most passes through the spark cycles, the ignition system of the present invention has been found to deliver adequate sparks at every cycle regardless of how slowly the starter turns the engine.

With the system here described, the distributor contacts require merely slight adjustment due to mechanical wear at infrequent intervals. Such a system has the effect of reducing atmospheric pollution and enables the engine to run smoother and gain full power. It also diminishes greatly the radio interference noise caused by distributor contacts. Also, in conventional ignition units, the condenser connected across the distributor points causes lingering transformer coil oscillations to occur. Since the current relay switch of the present invention is not dependent upon the condenser to gain a fast collapse and high voltage buildup in the transformer coil secondary, oscillations of this sort are negligible. This permits the dwell or current buildup time to be increased or extended to further aid the coil transformer to build and discharge a higher voltage at high operating speed.

Another desirable feature is that the inductor current relay switch described herein employs all ignition components, including coil and distributor, as built on the engine at the factory. Also, tachometers, Oscilloscopes, or other ignition testing instruments, when connected to the cold side of the coil of the transformer of the system herein, will function normally and without modification.

Although the present system employing transistorized switching has been applied herein to application in an internal combustion engine, it is to be understood that the system is adaptable to other applications wherein an inductor current is available.

In the case of positive-grounded cars, it, of course, would be necessary to change the polarity of the transistors as well as the voltage source. Otherwise, the switch system would be applicable as described.

I claim:

1. An inductor relay switch ignition system for a internal combustion engine, comprising in combination:

a primary coil forming part of an ignition coil for said system;

a source of DC. potential having the first pole thereof connected to one side of said primary coil;

first transistor switching means connected to the second side of said primary coil;

a pair of breaker points connected between the output of said first transistor switching means and a point electrically common with the second pole of said D.C. source;

second transistor means connected in parallel with said first transistor switching means, the output of said second transistor means bypassing said breaker points and being connected to said common point;

first biasing means biasing said first transistor switching means for immediate conduction upon closing of said breaker point;

second biasing means connected at least in part between the output from said first transistor switching means and a bias control point at said second transistor switching means, for biasing said second transistor switching means to conduction upon the occurrence of an output at said first transistor switching means;

said second transistor switching means having a lower impedance when conducting than said first transistor switching means, whereby current through said breaker points is relatively low, said second transistor switching means thereby carrying the bulk of the primary coil current.

2. A system in accordance with claim 1, wherein said second transistor switching means comprises two series-connected transistors, said second biasing means including a connection between the output from said first transistor switching means and the base of the second series-connected transistor of said second transistor switching means.

3. A system in accordance with claim 2, further including a neon lamp connected across the inputs of said parallel first and second transistor switching means, to protect said switching means against inductive kickback from said primary coil, and to provide visual indication of operation of said ignition system. 

1. An inductor relay switch ignition system for a internal combustion engine, comprising in combination: a primary coil forming part of an ignition coil for said system; a source of D.C. potential having the first pole thereof connected to one side of said primary coil; first transistor switching means connected to the second side of said primary coil; a pair of breaker points connected between the output of said first transistor switching means and a point electrically common with the second pole of said D.C. source; second transistor means connected in parallel with said first transistor switching means, the output of said second transistor means bypassing said breaker points and being connected to said common point; first biasing means biasing said first transistor switching means for immediate conduction upon closing of said breaker point; second biasing means connected at least in pArt between the output from said first transistor switching means and a bias control point at said second transistor switching means, for biasing said second transistor switching means to conduction upon the occurrence of an output at said first transistor switching means; said second transistor switching means having a lower impedance when conducting than said first transistor switching means, whereby current through said breaker points is relatively low, said second transistor switching means thereby carrying the bulk of the primary coil current.
 2. A system in accordance with claim 1, wherein said second transistor switching means comprises two series-connected transistors, said second biasing means including a connection between the output from said first transistor switching means and the base of the second series-connected transistor of said second transistor switching means.
 3. A system in accordance with claim 2, further including a neon lamp connected across the inputs of said parallel first and second transistor switching means, to protect said switching means against inductive kickback from said primary coil, and to provide visual indication of operation of said ignition system. 